Last year's Cheltenham Gold Cup winner Don Cossack has been retired after suffering a setback, trainer Gordon Elliott has announced.

Don Cossack was beaten just twice in 12 starts since October 2014 and connections had been making bullish noises recently about a return.

"It's a real sickener for Gigginstown, myself, (jockey) Bryan Cooper and the whole yard," Elliott said.

"We knew it was never certain we would get him back to the racecourse and even after that, to get him back to his best, but we were hopeful.

"He's a horse of a lifetime and he owes us nothing. I said all season that if he had any sort of setback at all we would not abuse him and retire him straight away.

"He's won Grade Ones at Cheltenham, Aintree, Punchestown, Fairyhouse and Down Royal.

"He was the top-rated horse in Britain and Ireland for the last two seasons.

"It was one of the highlights of my career when Don Cossack won the Gold Cup for us last year and he retires a champion. As I said already, he owes us absolutely nothing and a peaceful retirement awaits him out in Gigginstown."

Don Cossack's retirement means neither of the past two Gold Cup winners are in contention for the prize this year, with 2015 winner Coneygree ruled out of the race earlier in the week.